Reed for a loom



L. TE STRAKE REED FOR A LOOM Sept. 3, 1 968 3 Sheets-Sheet 1 Filed NOV. 2, 1965 L. TE STRAKE REED FOR A LOOM Sept. 3, 1968 3 Sheets-Sheet 2 Filed Nov. 2, 1965 L. TE STRAKE REED FOR A LOOM Sept. 3, 1968 Filed NOV. 2, 1965 3 Sheets-Sheet 3 United States PatcntQ 3,399,701 REED FOR A LOOM Lambertus te Strake, Deurne, Netherlands, assiguor to N .V. Machinefabriek L. te Strake, Deurne, Netherlands.

a Dutch company 4 f 1 Filed Nov. 2, 1965, Ser. No. 506,066 1 i Claims priority, application lletherlands, Nov. 3, .1964, 6412786 3.Claims. (Cl. 139188) ABSTRACT OF THE DISCLOSURE A reed for a jet-operated loom, comprising upper and lower bars that support reed blades, upper and lower covers which extend from the beating sides of the upper and lower bars, respectively; which have converging opposed surfaces for delimiting the upper and lower mats of warp threads forming the shaft; and which have closely spaced outer edges extending adjacent to the woven fabric, the reed being mounted to pivot upon an axis which is substantially spaced, on the fabric side, from a plane which is perpendicular to the fabric and passes through the beaten edge of the fabric, so that during the beating movement of the reed, the lower cover passes just below the lower mat of warp threads and below the fabric and the upper cover is lifted off the upper mat of warp threads and the fabric.

Background of the invention The invention relates to improvements in or relating to a reed for a loom, in which blades are provided between an upper bar and a lower bar of the reed; r

Increasing the production rate of a loom meets with numerous difliculties. First of all, it is impossible to increase the production rate when using a shuttle, because the operation thereof is too slow. So far, blowing a weft into the shed by means of compressed air has proven to be one of the most efiicient methods for increasing the production rate of a loom.

If one intends to blow a weft into the shed by means of compressed air, various measures are necessary to do this as rapidly as possible. The shape and size of the shed formed by the warp threads are very critical. Preferably, the shed is as small as possible, in order to maintain the opening of the warp threads and thereby the maximum locus of movement of the shafts reasonably small, whilst this limitation also makes possible a decrease of the reed stroke. On the other hand, the shed must not be too small, because this would entail the risk that the weft introduced in the shed may at its front end come into contact with the warp threads, whereby the weft becomes entangled and does not reach the other end of the shed.

Summary of the invention The invention aims at providing a reed with which a very small opening of the warp threads and thereby a very small shed can be attained, without running the risk that the weft may come into contact with the warp threads during its movement from one side of the shed towards the other side thereof.

According to the invention, this is attained in that one or more covers parallel to the bars of the reed are provided at the beating side of the reed, which covers extend in such a way from the reed, that they delimit the shed formed by the warp threads outside these warp threads. In this way, a substantially closed tunnel is obtained, in which an airjet of high velocity can be generated, without an excessively large quantity of air leaving the shed in transverse direction, such as between the warp threads.

According to a preferred embodiment, the opposed sides of the covers on top of and below the shed converge in the direction away from the reed and delimit a narrow slot between them, for passing the warp threads or the produced fabric. 1 In this way, a shed is obtained which constitutes a closedtunnel and in which no air can leak off between the warp threads at the upper or the lower side of the shed;

Further, the opposed surfaces of the upper cover and the lower cover are 'so positioned, that in the opened position of the shed, these surfaces are parallel to the upper mat of warp threads and the lower mat of warp threads respectively and that the confronting surfaces of the upper cover and the lower cover serve as stops for the upper warp and the lower warp respectively ofthe shed.

The small deviation of the shed opening which occurs with the warp threads and which could give rise to turbulence of the air fiow in the shed or due to which the weft could enter into contact with the warp threads at the interior, is thereby eliminated.

Preferably, the reed is so designed, that the cover at the upper side of the shed is made from transparent material. There-by, it is possible to observe the interior of the shed, e.g. for checking whether a weft is located entirely within the shed. This observation possibility can be improved if the cover on top of the shed is so designed that this constitutes a cylinder lens, the axis of which is parallel to the bars of the reed. An advantage thereof is, that the warp threads, which are an obstacle for the observation of the weft, are not magnified, whereas the weft can be subjected to a considerable magnification. The invention will be further elucidated below with reference to the drawing, which shows an embodiment of a device according to the invention.

Brief description of the drawings FIGURE 1 is an isometric elevation of a reed according to the invention.

FIGURE 2 is a diagrammatical elevation of the reed as shown in FIGURE 1 in a position in which the reed enters into contact with the fabric as well as in a position in which a weft can be blown into the shed.

FIGURE 3 is a perspective view of a loom provided with a pneumatic device for weft insertion on which loom a reed according to the invention can be used.

Description of the preferred embodiments The reed comprises a heavy tube 1 extending transverse to the loom below the fabric and the warp threads as shown in FIG. 2, to which tube the slay swords 2a and 2b are attached. FIGURE 2 shows the location of the axis 1a of the heavy tube 1, relative to a plane 9a that is perpendicular to the fabric and passes through the beaten edge 9b of the fabric.

The slay swords can be very short in order to impart a certain toppling movement to the reed, and in order to minimize the forces acting on the reed due to its inertia during the rapid reciprocating movement, such as 400 strokes per minute. The slay swords 2a and 2b carry the lower bar 3 and the upper bar 4 of the reed, which bars will not be described in detail, since they do not constitute a major part of the invention.

Between the bars 3 and 4, the blades 5 of the reed are arranged in a manner known per se. In the illustrated embodiment, the blades are somewhat arcuate, in order to keep the upper angle and the lower angle with respect to the warp threads equal to each other.

Covers 6 and 7 respectively are arranged parallel to the bars 3 and 4 of the reed. These covers extend so far from the reed constituted by the blades 5, that they completely cover the warp threads of the shed.

The covers 6 and 7 delimit a narrow slot 8 in the direction of the fabric, through which slot the fabric can pass when the reed meets its stop, as has been shown in FIGURE 2. The opposed surfaces 10 and 11 of the covers 6 and 7 respectively are flat and are parallel to the lower mat of warp threads 12 and the upper mat of Warp threads 13 respectively. The position of these surfaces 10 and 11 is such that the warp threads 12 rest against the surface 10 and the warp threads 13 rest against the surface 11 when the reed is in its completely withdrawn position. This withdrawn position has been shown in FIGURE 2 by thin lines. In this way, it is possible to obtain a shed with dimensions of no more than 18 ml. by 13 ml., e.g. the height of the shed is only 13 ml. and the depth of the shed, e.g. the perpendicular distance of the reed from the fabric is only 18 ml. Notwithstanding these small dimensions, which until now could not be realized, the weft does not enter into contact with the Warp threads, because the warp threads lie against the surfaces 10 and 11.

Because of the location of the axis of rotation of the slay swords 2a and 2b, which coincides with the axis 1a of the tube 1, the cover 6 can pass just below the lower mat of warp threads 12 and below the fabric 9, whilst the upper cover 7 is lifted off the mat of warp threads and the fabric.

Preferably, the cover 7 is transparent, so that the shed can be observed through the upper face 14 of the cover. If this face 14 is arcuate, as has been shown with a dotted line 15, the cover 7 constitutes a cylinder lens, which projects a large amount of light into the shed and which makes it possible to observe the weft in a magnified condition. Preferably, the surface 10 has a colour which markedly deviates from the colour of the warp threads and the weft.

In the loom according to FIGURE 3 the warp threads 12 and 13 are visible. Further a pneumatic weft inserting apparatus is generally indicated with the reference nu- 4 meral 16. The slay swords 2a and 211 support the upper bar 4 for the blades 5.

I claim:

1. Reed for a jet-operated loom comprising upper and lower bars that support reed blades, wherein the improvement comprises upper and lower covers which extend from the beating sides of the upper and lower bars, respectively; which have converging opposed surfaces for delimiting the upper and lower mats of warp threads forming the shed; and which have closely spaced outer edges extending adjacent to the woven fabric, the reed being mounted to pivot upon an axis which is substantially spaced, on the fabric side, from a plane which is perpendicular to the fabric and passes through the beaten edge of the fabric, so that during the beating movement of the reed, the lower cover passes just below the lower mat of warp threads and below the fabric and the upper cover is lifted off the upper mat of warp threads and the fabric.

2. Reed according to claim 1 wherein the upper cover is made of transparent material.

3. Reed according to claim 2 wherein the upper cover forms a cylindrical lens the axis of which is parallel to the bars of the reed.

References Cited UNITED STATES PATENTS 1,721,940 7/1929 Ballou 139127 2,279,759 4/1942 Moore 139-12 3,229,725 1/1966 Saito 139127 2,480,645 8/1949 Gourlay 139-193 FOREIGN PATENTS 189,478 5/ 1964 Sweden. 745,345 2/ 1956 Great Britain.

MERVIN STEIN, Primary Examiner.

I. KEE CHI, Assistant Examiner. 

